Refrigeration



March 30, 1943; c, C coo s' 7 2,315,364

REFRIGERATION Filed Aug. 20, 1958 INVENTOR Carils C, Coons ATTORNEY.

Patented Mar. 30, 1943 .UNITQE'D STATES PATENT orr ce REFRIGERATION Curtis 0. Coons, .North The Hoover Company,

corporation of Ohio anton, Ohio, assignor to North Canton, Ohio. a

Application August 20, 1938, Serial No. 225,873

(Cl. Gil-119.5)

21 Claims.

tion liquid has a higher boiling point than the refrigerant, the refrigerant vapors can be separated from the absorption solution by the application of heat. But in spite of the difference in the boiling temperatures of the two mediums, some of the absorption solution passes off as vapor along with the refrigerant vapor. Unless some means is provided for separating the absorbent vapor from the refrigerant vapor, the operation as well as the efficiency of the machine is impaired.

One method of separating the two vapors is by theuse of an analyzer, in which strong solution from the absorber is brought into contact with the hot mixture of vapors leaving the boiler under such conditions that the absorbent vapor is condensed and the heat of condensation is utilized to distill ammonia vapor from the strong solution as it returns to the boiler.

Itis accordingly an object of this invention to provide a boiler-analyzer-solution-heat-exchanger assembly in which the heat contained in the products of combustion exhausted from the boiler is not only used to heat the outside of the boiler,

. but the analyzer column as well, and-to provide .ing such a machine to a domestic refrigerator cabinet.

It is accordingly another object of this invention to provide a compact boiler-analyzer-solution-heat-exchanger assembly which can be applied easily to a domestic refrigerator cabinet without taking up excessive space.

Since variations in room temperature and in the burner render it most difficult to .maintain the analyzer temperature within the required critical range, my invention also makes provision for diluting the products of combustion with room air in accordance with the temperature conditionswi ana er itself. 7

Other objects A d advantages will become apparent as the description proceeds, when taken in connection with the accompanying drawing in which the single figure diagrammatically shows a continuous absorption refrigerating apparatus with the boiler-analyzer-solutionheat-exchanger assembly shown in detail.

The refrigerating apparatus has" a boiler I0,

condenser II, evaporator l2, motor l3, fan l4, and an absorber l5 connected in circuit by suitable conduits in a well known manner. paratus may be charged with ammonia as refrigerant, water as the absorbent medium, and an inert pressure equalizing medium, such as nitrogen. Heat is applied to the boiler 10 by means of a gas burner 16, and the products of combustion pass horizontally through the flue l'l into a jacket l8 surrounding the boiler l0 and the analyzer column l9, pass back over the outside of the boiler l0 and upwardly around the analyzing a column l9 and out the stack, not shown.

The ammonia is absorbed in the absorbent liquid and the application of heat to the boiler 1 0 drives off the ammonia vapor from the absorbent liquid. This ammonia vapor and a small amount of absorbent vapor bubbles upwardly through the analyzing column I9 in counterflow to rich, relatively cool absorption solution returning from the absorber l5. As the rich, cool solution comes incontact with the hot vapors, the absorbent vapor is' condensed and its, heat of condensation serves to heat the rich solution and to liberate ammonia vapor therefrom. Bafiie plates are provided in the analyzer column so that the rich absorption solution flowing down overthem can come in better contact with the rising hot vapors.

The refrigerant vapor and any absorbent vapor still mixed therewithflows upwardl'ythrough pipe 2| to rectifier 22 where the remainder of the absorption vapor condenses and flows backwardly to the boiler, and the ammonia vapor, continues to .the condenser H where it is liquefied and then flows to the evaporator l2 through pipe 23. r

The. weakened absorbent solution leaves the boiler ID by pipe 24, passes through the inner coil of the solution heat exchanger 25, and is raised to the top of the absorber I5 by gas lift pump 26 which is operated by gas from the discharge side of thegas pump flowing through pipe 21 into the gas lift pump 26 which is comparatively small in diameter so that the gas will lift slugs of absorption solution to the top of the absorber. The lean absorption solution flows downwardly through the absorber by gravity and returns to the boiler by way of solution reservoir 28, pipe 29, the outer pass of the solution heat exchanger 25, and analyzing column l9.

The fan It circulates an inert evaporation accelerating medium, such as nitrogen, in a closed circuit between the evaporator and absorber.

The ap- The inert gas leaving the discharge side of the pump by pipe 30, flows through the outer pass of gas heat exchanger 3 I, to the bottom of the evaporator by pipe 32 and upwardly itherethrough in counterflow to liquid refrigerant entering the evaporator by pipe 23. The refrigerant difl'uses into the :inert medium producing refrigeration.

the refrigerant vapor is absorbed out of the mixture, and the inert medium returns to the suction side of the fan I 4. r

A small dam 33'is provided in the upper tube of the evaporator to prevent liquid refrigerant from flowing down the gas circuit into the gas heat exchanger and a drain 34 leads from the bottom coil of the evaporator to the strong absorption solution pipe 29 so as to drain any residue or unevaporated solution away from the evaporator. A vent pipe 35 connects the top of pipe 24 to the top of the absorber so as to prevent a gas pocket forming in 'the solution heat exchanger.

The boiler analyzer solution heat exchanger assembly is embedded in insulation 36 and the solution heat exchanger surrounds the analyzing column as shown. 7

Since the solution heat exchanger surrounds the analyzing column, the flue surrounds the boiler and analyzer column and the whole assembly is embedded in insulation, a very compact unit is formed which takes up a minimum of space and in which a minimum amount of insulation conserves a maximum amount of heat. The compactness of the assembly is very advantageous when a machine of this type is applied to a domestic refrigerator since space is at a premium.

In order to provide a more accurate control of the analyzer temperature, a duct 31 leads into the space around the analyzer and is provided with a valve 38 operated by bellows motor 39 connected by tube 40 to thermostatic bulb ll positioned in the top of the analyzing column. As the temperature of the analyzing column approaches the critical temperature (it the refrigerant, it expands a fluid in the bulb 4| which operates the bellows motor 39 to open the valve 38 and allow air to enter through duct 31 and mix with the products of "combustion flowing upwardly in the space about the analyzing column. Should this result in a lowering of the analyzer temperature toward the critical temperature of the absorbent vapor, the damper is closed slightly by the bellows to decrease the influx of room air to jacket I8.

Thus, it will be clear that the mixing of air with the products of combustion maintains the analyzing column at a uniform temperature so that it does not get so warm as to allow absorbent vapor to pass outwardly along with the refrigerant vapor, and neither'is it permitted to become so cool as to condense refrigerant vapor. serves to prevent condensation of moisture out of the products of combustion by diluting the same with unsaturated room air.

From the foregoing it will be appreciated that I have provided a hovel boiler-analyzer-solutionheat-exchanger assembly for an absorption re- It also frigerating system which is more efllcient and compact than any construction heretofore proposed, as well as one which is exceedingly simple in construction and operation, and one which is fully automatic.

., by the scope of the claims.

While I have shown and described one modiflcation of my invention, it is to be understood that this embodiment is to be taken as illustrative only and not in a limiting sense. I do not wish to be limited to the structure shown but to include all equivalent variationsthereof I claim:

1. An absorption refrigerating apparatus comprising, a horizontally arranged boiler having an upwardly extending analyzer column associated therewith, means for heating said boiler by means of a combustible fuel and means for di-- recting products of combustion overthe exterior of the boiler and upwardly over the analyzing column.

.2. An absorption refrigerating apparatus comprising, a boiler, an analyzer 'column associated therewith, means for heating said boiler by means of a combustible fuel, means for directing the products of combustion over the exterior of the boiler and analyzer column, and means for leading air into the products of combustion flow-' ing over the analyzer column.

3. An absorption refrigerating apparatus comprising, a boiler, an analyzer column associated therewith, means for heating said boiler by means of a combustible fuel, means for directingthe products of combustion over the exterior of the boiler and analyzer column, means for leading .air into the products of combustion flowing over the analyzing column, and means for controlling said air supply.

4. An absorption refrigerating apparatus comprising, a boiler haying an internal flue, an analyzer column associated therewith, means for heating said boiler by means of a combustible fuel burning in said internal flue, and means for leading the products of combustion over the exterior of the boiler and over the analyzing column.

5. An absorption refrigerating apparatus comprising, a boiler having an internal flue, an ana yzer column associated therewith, means for heating said boiler by means of a combustible fuel burning in said internal flue. means for leading the products of combustion over the exterior of the boiler and over the analyzer column, and means for leading air into the products of combustion flowing over the analyzing column.

6. An absorption refrigerating apparatus comprising, a boiler having an internal flue, an analyzer column associated therewith, means for heating said boiler by means of a combustible fuel burning in said internal flue, means for leading the products of combustion over the exterior of the boiler and over the analyzing column, means for leading air into the products of combustion flowing over the analyzing column and 7. An absorption refrigerating apparatus comprising, a horizontally arranged boiler, an an-' alyzer column associated therewith and extend ing vertically therefrom. and a solution heat exchanger located above said boiler and encircling said analyzing column to form a compact boileranalyzer heat exchanger assembly, said assembly beingembedded in insulation. 8. An absorption refrigerating apparatus comprising, a boiler, an analyzer column associated therewith, a solution heat exchanger encircling said analyzing column to form a boiler-analyzer heat exchanger assembly, said assembly being embedded in insulation, means for heating said except as limited boiler by means of a combustible fuel, and means for directing the products of combustion over the boiler and analyzer column.

9. An absorption refrigerating apparatus comprising, a boiler, an analyzer column associated therewith, a solution heat exchanger encircling said analyzer column to form a boiler-analyzer.

heat exchanger assembly, said assembly being embedded in insulation, means for heating said boiler bymeansof combustible fuel, means for directing products of combustion over the boiler and analyzer column, means for leading air from theexterior of said insulation into the products said boiler-analyzerassembly, and communicating with said flue, whereby the products of com: bustion are led overthe exterior of said boiler and analyzer.

11. An absorption refrigerating apparatus comprising, a boiler, an analyzer column associated with said boiler, a condenser, an evaporator, an absorber, means for circulating inert medium in a closed circuit between the evaporator and absorber and to utilize a'portion of said inert medium to circulate the absorption solution in a closed circuit between the boiler and absorber, means to heat the boiler by means of combustible fuel, and a jacket surrounding.

said-boiler and analyzing column'whereby the products of combustion are led over the exterior of the boiler and analyzer column. i

12. An absorption refrigerating apparatus comprising, a boiler, an analyzer column associated therewith, a condenser, an evaporator, an absorber, means to circulate inert medium in a sorbet and to utilize a portion of said inert medium to circulate the absorption solution in a closed circuit between the boiler and absorber,

-means to heat the boiler by means of combustible fuel, a jacket surrounding said boiler and analyzing'column whereby the products of combustion are led over the exterior of the-boiler and analyzing column, and means to lead air into the productsof combustion flowing over the analyzing column.

13. An absorption refrigerating apparatus the products of combustion flowing in heat exchange with the analyzer.

15. An absorption refrigerating apparatus comprising, a boiler, an analyzer, means for heating said boiler by means of a combustible fuel, means for leading the products of combustion into heat exchange relationship with said analyzer, means for supplying atmospheric air into the products of combustion flowing in heat exchange with the analyzer and means for controlling said. air supply.

16. An absorption refrigerating apparatus comprising, a boiler, an analyzer, means for heating said boiler by means of a combustible fuel, means for leading the products of combustion into heatexchange relationship with said analyzer, means for supplying atmospheric air into the products of combustion flowing in heat exchange with the analyzer, and means for controlling said air supply, said control means being responsive to analyzer temperature.

1'7. An absorption refrigerating apparatus comprising, a boiler, an analyzer column associated therewith, means for heating said boiler by means of a combustible fuel, means for direc'ting the products of combustion over the exterior of the boiler, and means for leading a mixture of atmospheric air and the products of combustion over the analyzer column.

18. An absorption refrigerating apparatus comprising, an elongated horizontally positioned boiler having a combustion flue extending horizontally therethrough, an analyzer column extending upwardly from said boiler at one end thereof, a gas burner positioned to discharge .its flame into said flue at the analyzerend thereof, and means communicating with the discharge end of said flue for conducting flue gases into heat exchange with the exterior of said boiler and analyzer. 1

19. An absorption refrigerating apparatus comprising, aho'rizontal boiler, an analyzer col- I umn in open communication therewith, means closed circuit between the evaporator and ab- I comprising, a horizontal boiler, an analyzer extending upwardly therefrom and in open communication therewith, means for heating said boiler by means of a combustible fuel, means for leading absorption solution through said analyzer in counterflow to vapors flowing'upwardly therethrough and means for leading the products of combustion into heat exchange relation with said analyzer.

14. An absorption refrigerating apparatus I comprising, a boiler, an analyzer, means for heatfor heating said boiler, means for leading absorption solution through said analyzer column in counterflow to vapors flowing therethrough, means forleading air over said analyzer column and means for controlling said last mentioned 20. An absorption refrigerating apparatus comprising, a horizontal boiler, an analyzer column'in open communication therewith, means for heating said boiler, means for leading absorption solution through said analyzer column in counterflow to vapors flowingtherethrough, means for leading airover said analyzer, and means for controlling said last mentioned means, said control means being responsive to the temperature of said analyzer column.

21. An absorption refrigerating apparatus comprising, a boiler normally filled with a solution of refrigerant in an absorbent, a jacket spaced from and surrounding said boiler, said in: said boiler by means of a combustible fuel,

- means for leading the products of combustion into heat exchange relation with said analyzer, and means for supplying atmospheric air into boiler having an internal flue extending therethrough and communicating with said jacket at one end, and means for heating 'said boiler by means of a combustible fuel burning in said flue, whereby the products of combustion are led through saidv flue in one direction and reversely over the exterior of said boiler.

- CURTIS C. COONS. 

